| 1. | EXECUTIVE SUMMARY |
| 1.1. | Report Overview |
| 1.2. | Executive Summary (1) - Key Market Takeaways |
| 1.3. | Executive Summary (2) - Key Technical Findings |
| 1.4. | Hydrogen Combustion Engines - Older Than the Diesel Engine |
| 1.5. | H2ICE for Hard to Abate Sectors |
| 1.6. | H2ICE, Why Now? |
| 1.7. | H2ICE Offers Continuity With Current Drivetrains |
| 1.8. | The Messy Middle - a Period of Great Change |
| 1.9. | Overview of Powertrain Options |
| 1.10. | Chemical Reaction - Gasoline, Hydrogen & Fuel Cells |
| 1.11. | Key Technical Differences Between Petrol and Hydrogen ICEs |
| 1.12. | Hydrogen Combustion is Not Zero Emissions |
| 1.13. | NOx Formation Mechanisms - a Summary |
| 1.14. | Strategies to Reduce NOx in Hydrogen Engines |
| 1.15. | Real World H2ICE NOx Performance |
| 1.16. | Energy Density of Hydrogen |
| 1.17. | Options for Onboard Hydrogen Storage |
| 1.18. | FCEV and H2ICE Range Comparisons |
| 1.19. | Fuel Volume and Mass Requirements |
| 1.20. | Volumetric Density of Fuels - Comparison |
| 1.21. | Costs at the Pump - Hydrogen Has a Premium |
| 1.22. | System Efficiency - BEV, FCEV & H2ICE |
| 1.23. | Industry Landscape - H2ICE |
| 1.24. | Suppliers Hedge Their Bets |
| 1.25. | Is H2ICE a Fast-to-Market Solution? |
| 1.26. | H2ICE Contradiction |
| 1.27. | Hydrogen Combustion Engine, ZEV (Zero-emission Vehicle) or Not? |
| 1.28. | H2-ICE, BEV and FCEV Summary Table |
| 1.29. | H2ICE Drivers & Barriers to Adoption |
| 1.30. | Forecast Summary - Sector Split |
| 1.31. | H2ICE Forecasts - Market Shares |
| 1.32. | HD Truck Market by Drivetrains, 2025-2045 |
| 1.33. | H2ICE Forecasts - Market Value |
| 2. | INTRODUCTION TO HYDROGEN COMBUSTION |
| 2.1. | Hydrogen Combustion Engines - Older Than the Diesel Engine |
| 2.2. | H2ICE, Why Now? |
| 2.3. | H2ICE for Hard to Abate Sectors |
| 2.4. | H2ICE, Why Now? |
| 2.5. | H2ICE Offers Continuity With Current Drivetrains |
| 2.6. | Overview of Powertrain Options |
| 2.7. | The Messy Middle - a Period of Great Change |
| 2.8. | Hydrogen Combustion Engine, ZEV (Zero-emission Vehicle) or Not? |
| 2.9. | Industry Landscape - H2ICE |
| 2.10. | Selection of OEMs and Tier-1s with H2ICE Projects |
| 2.11. | Is H2-ICE a Fast-to-Market Solution? |
| 2.12. | H2ICE Contradiction |
| 2.13. | H2-ICE, BEV and FCEV Summary Table |
| 2.14. | Hydrogen Combustion System Layouts |
| 2.15. | H2ICE CAPEX Advantage - Industry Figures |
| 2.16. | Is there a TCO case for H2ICE? - (1) |
| 2.17. | Is there a TCO case for H2ICE - (2) |
| 2.18. | Li-ion Cost Improvements |
| 3. | H2ICE OUTLOOK BY SECTOR |
| 3.1. | H2ICE Sector Commentary |
| 3.1.1. | Commercial Segment Emerges as the Key Opportunity for H2ICE |
| 3.1.2. | H2ICE Prototypes - Genuine Interest or Ploy for Funding |
| 3.2. | Trucking |
| 3.2.1. | Commercial Segments with H2ICE Draw - Trucking |
| 3.2.2. | Long Haul Trucking - H2ICE Solves Many Pain Points |
| 3.2.3. | MAN - Limited H2ICE Production Run |
| 3.2.4. | Mercedez Truck - H2 Powered Unimog |
| 3.2.5. | KEYOU |
| 3.2.6. | DAF BEV, H2-ICE, and FCEV |
| 3.2.7. | Southwest Research Institute Consortium |
| 3.2.8. | SwRI - a Converted H2 Class-8 Truck |
| 3.2.9. | Tata Motors H2-ICE Truck |
| 3.2.10. | Cummins Inc. - Fuel Agnostic Engine Lineup |
| 3.2.11. | Cummins H2-ICE Approach |
| 3.2.12. | Industry Converges on Standards for H2ICE Trucks |
| 3.3. | Non-Road Mobile Machinery |
| 3.3.1. | Commercial Segments with H2ICE Draw - NRMM |
| 3.3.2. | Options for NRMM |
| 3.3.3. | Diverse Strategy from Many OEMs |
| 3.3.4. | JCB - "Powertrain Selection for Net Zero Construction Equipment" |
| 3.3.5. | CAM Drivetrain Suitability |
| 3.4. | Cars |
| 3.4.1. | Passenger Cars |
| 3.4.2. | Toyota - BEV Reluctance Continues in H2-ICE |
| 3.4.3. | FAW - Hydrogen Engine Tests |
| 3.4.4. | Supercars & Hypercars - Low Volume High Performance Segment |
| 3.4.5. | Supercar Manufacturers Dodge ICE Ban in Europe |
| 3.4.6. | Impact of Regulations on Supercar Manufacturers |
| 3.4.7. | Supercars at the Forefront of Innovation |
| 3.4.8. | Performance Oriented H2ICE |
| 3.5. | Aviation |
| 3.5.1. | Aviation |
| 3.5.2. | Power Requirements for Green Hydrogen in Aviation |
| 4. | TECHNICAL ASPECTS OF HYDROGEN INTERNAL COMBUSTION ENGINES |
| 4.1. | Introduction to Combustion Engines |
| 4.2. | Combustion Chamber For a Four-Stroke Spark Ignition Engine |
| 4.3. | Chemical Properties of H2 |
| 4.4. | Key Technical Differences Between Petrol and Hydrogen ICEs |
| 4.5. | Chemical Reaction - Gasoline, Hydrogen & Fuel Cells |
| 4.6. | Air to Fuel Ratio - an Overview |
| 4.7. | Air to Fuel Ratio for Hydrogen vs Petrol |
| 4.8. | Rich, Stochiometric or Lean for Hydrogen Engines |
| 4.9. | Ignition Energy |
| 4.10. | Auto-ignition Temperature |
| 4.11. | Flame Speed |
| 4.12. | Diffusivity |
| 4.13. | Quenching Distance |
| 4.14. | Injection Strategies |
| 5. | TAILPIPE EMISSIONS OF A HYDROGEN COMBUSTION ENGINE |
| 5.1. | Tailpipe Emissions - Overview |
| 5.2. | H2ICE- Motor Oil Emissions Assessment |
| 5.3. | Hydrogen Combustion is Not Zero Emissions |
| 5.4. | NOx - the Big Question for Hydrogen Emissions |
| 5.5. | Hydrogen Combustion and NOx Formation |
| 5.6. | NOx Formation Mechanisms - a Summary |
| 5.7. | Engine Speed and NOx |
| 5.8. | NOx Emissions in H2ICE - Academic Studies |
| 5.9. | NOx in Diesel/Hydrogen Dual Fuel |
| 5.10. | Studies Produce Conflicting Results for Dual-Fuel |
| 5.11. | NOx in Gasoline Dual Fuel - Effect of Lambda |
| 5.12. | Approaches to Limiting NOx in Current Vehicles |
| 5.13. | Overview of Catalytic Converters |
| 5.14. | Exhaust Gas Recirculation (EGR) |
| 5.15. | Lean NOx Trap |
| 5.16. | Selective Catalytic Reduction |
| 5.17. | Strategies to Reduce NOx in Hydrogen Engines |
| 5.18. | Three-Way Catalysts for Hydrogen Engines |
| 5.19. | LNT for Hydrogen Engines |
| 5.20. | SCR for Hydrogen Engines |
| 5.21. | Toyota Explores Direct Water Cooling |
| 5.22. | EGR for Hydrogen Engines |
| 5.23. | NOx Emissions for Passenger Vehicles |
| 5.24. | NOx Emissions for Heavy Duty Vehicles |
| 5.25. | Real World H2ICE NOx Performance |
| 5.26. | NOx Emissions - Aviation |
| 5.27. | Contrail Emissions - Aviation |
| 6. | HYDROGEN AS A FUEL |
| 6.1. | Hydrogen Overview |
| 6.1.1. | IDTechEx's Hydrogen Research Portfolio |
| 6.1.2. | Hydrogen as Fuel - Overview |
| 6.1.3. | Energy Density of Hydrogen |
| 6.1.4. | Hydrogen as Fuel - Overview |
| 6.1.5. | Hydrogen as a Fuel |
| 6.1.6. | The Hydrogen Economy |
| 6.2. | Production and Costs of Hydrogen |
| 6.2.1. | Hydrogen: Emissions & Cost Issues |
| 6.2.2. | The Colours of Hydrogen |
| 6.2.3. | The colors of hydrogen |
| 6.2.4. | State of the hydrogen industry - Green Hydrogen is a Small Fraction |
| 6.2.5. | Traditional hydrogen production |
| 6.2.6. | Removing CO₂ emissions from hydrogen production |
| 6.2.7. | Main electrolyzer technologies |
| 6.2.8. | Future trend of the electrolyzer market |
| 6.2.9. | Important competing factors for the green H2 market |
| 6.2.10. | Green Hydrogen Production Costs |
| 6.2.11. | H2 Fuel Price More than Production Cost |
| 6.2.12. | On-site H2 Production in Europe |
| 6.2.13. | Passenger Car CO₂ Emissions - H2ICE, FCEV, BEV & Fossil Fuels |
| 6.2.14. | Cost of Hydrogen at the Pump (1/2) |
| 6.2.15. | Cost of Hydrogen at the Pump (2/2) |
| 6.2.16. | Costs at the Pump - Hydrogen Has a Premium |
| 6.2.17. | Required Hydrogen Price for Gasoline Parity |
| 6.3. | Distribution & Refueling Infrastructure |
| 6.3.1. | Distribution & Refueling Overview |
| 6.3.2. | H2-ICE & FCEV - an Opportunity for Parallel Infrastructure Rollout? |
| 6.3.3. | Overview of distribution methods |
| 6.3.4. | Hydrogen distribution methods by stage of development |
| 6.3.5. | Transporting Hydrogen Requires More Trailers |
| 6.3.6. | Hydrogen refueling stations (HRS) |
| 6.3.7. | HRS Sizing Depends on Usage |
| 6.3.8. | Toyotas HRS Approach |
| 6.3.9. | Alternative hydrogen refueling concepts |
| 6.3.10. | Available Hydrogen Infrastructure by Region |
| 6.3.11. | State of hydrogen refueling infrastructure worldwide (1/2) |
| 6.3.12. | State of hydrogen refueling infrastructure worldwide (2/2) |
| 6.3.13. | Hydrogen Refuelling Infrastructure - Europe |
| 6.3.14. | Europe TEN-T Core Network |
| 6.3.15. | H2ICE Contradiction |
| 6.3.16. | HRS in the USA Limited to California |
| 6.3.17. | The Clean Energy Partnership |
| 6.3.18. | LIFTE H2: higher pressure transportation is needed |
| 6.3.19. | LIFTE H2: Mobile H2 refuelers are more competitive |
| 6.3.20. | Infrastructure Costs - BEV vs Hydrogen |
| 6.4. | Onboard Storage |
| 6.4.1. | Options for Onboard Hydrogen Storage |
| 6.4.2. | Hydrogen storage methods by stage of development |
| 6.4.3. | Options for Physical Hydrogen Storage |
| 6.4.4. | Compressed hydrogen storage |
| 6.4.5. | Geometries and Limitations of Storage Methods |
| 6.4.6. | Compressed storage vessel classification |
| 6.4.7. | Reduction in compressed cylinder weight |
| 6.4.8. | Compressed Hydrogen in HDVs |
| 6.4.9. | Compressed Hydrogen in LDVs |
| 6.4.10. | Forvia - Major Tier 1 Explores Rectangular Tanks |
| 6.4.11. | FCEV onboard hydrogen tanks |
| 6.4.12. | Liquid hydrogen (LH2) |
| 6.4.13. | Cryo-compressed hydrogen storage (CcH2) |
| 6.4.14. | BMW'S Cryo-compressed storage tank |
| 6.4.15. | Chemical Storage |
| 6.4.16. | Hydrogen Safety |
| 6.5. | Hydrogen Fuel Consumption & Range |
| 6.5.1. | Hydrogen Combustion Powered Vehicles |
| 6.5.2. | H2-ICE Efficiency vs FCEV |
| 6.5.3. | Real World Range Comparisons - H2ICE and FCEVs |
| 6.5.4. | Fuel Consumption |
| 6.5.5. | FCEV Range Improvements |
| 6.5.6. | Hydrogen Consumption Comparisons - FCEV and H2ICE |
| 6.5.7. | BEV, FCEV and H2ICE Comparisons |
| 6.5.8. | FCEV and H2ICE Range Comparisons. |
| 6.5.9. | H2 Storage Required for Parity - Racecar |
| 6.5.10. | Volumetric and Gravimetric Requirements for 1km |
| 6.5.11. | Volume Required for 1km Travelled |
| 6.5.12. | Volume and Weight Required - Tank Considerations |
| 6.5.13. | System Efficiency - BEV, FCEV & H2ICE |
| 6.5.14. | Well-to-Wheel Consumption |
| 7. | HYDROGEN EMBRITTLEMENT |
| 7.1. | Hydrogen embrittlement & mechanisms |
| 7.2. | Types of hydrogen embrittlement |
| 7.3. | Factors influencing H2 embrittlement |
| 7.4. | Effect of impurities on H2 embrittlement |
| 7.5. | Hydrogen embrittlement & compatible metal alloys |
| 8. | FORECASTS |
| 8.1. | H2ICE Drivers & Barriers to Adoption |
| 8.2. | Forecast Summary - Drivetrain Comparisons |
| 8.3. | Forecast Summary - Sector Split |
| 8.4. | Forecast Assumptions |
| 8.5. | H2ICE Forecasts - Unit Sales 2025-2045 (1) |
| 8.6. | H2ICE Forecasts - Unit Sales 2025-2045 (2) |
| 8.7. | H2ICE Forecasts - Regional Analysis |
| 8.8. | H2ICE Forecasts - Market Shares |
| 8.9. | HD Truck Market by Drivetrains, 2025-2045 |
| 8.10. | H2ICE Forecasts - Market Value |